If you right click the app then "show package contents" in the Finder then go to Resources > Contents there's a file with keybindings called keys.nu. You can s

If you right click the app then "show package contents" in the Finder then go to Resources > Contents there's a file with keybindings called keys.nu. You can see (sidemap setKey:"<c-d>" toAction:"scroll_downward:") (sidemap setKey:"<c-u>" toAction:"scroll_upwards:") So apparently they are planned, just not yet implemented. I haven't messed with the file much to see what else you can do with it, but I imagine there's a way to override it in .vimrc style and customize it.